HAMILTON, Ohio — A prosecutor has told a jury that a southwest Ohio pediatrician performed sex acts on three teen patients during office visits, slipping them cash payments as they left.

In opening statements Tuesday, Assistant Butler County Prosecutor Lance Salyers told jurors that 53-year-old Mark Blankenburg paid the boys as much as $200. Salyers said some victims continued to get payments and prescription drugs from Blankenburg as adults.

Defense attorney Mike Shanks told jurors there is no evidence Blankenburg committed the sex acts. He calls it a case of “flat-out extortion.”

He says the case revolves around a former patient who had drug problems and wanted money.

Blankenburg’s twin brother, also a pediatrician, is charged with similar sex crimes involving children. His trial is scheduled for April.